Cortical cataractous lenses will be classified by photographing technique. Each lens will be sectioned to thin slices 10 - 20 microns and about 10 sections of each lens will be studied by light scattering. Computer analysis of the light scattering patterns will evaluate a number of parameters as a function of the location within the lens and the classification of the cortical cataract. These parameters include a. the size of dense aggregates, b. the average separation between these aggregates, c. the volume fraction of the aggregates within the lens, d. the average refractive index difference between the aggregates and the surroundings. Similar four parameters describe the size and separation of birefringent units within the lens, their volume fractions and the difference in the average birefringence between these units and their surroundings. Fluorescent microscopic work will be done on the thin sections mapping the excitation and emission spectra as a function of cortical cataract. The photographic classification will be correlated with the light scattering and fluorescence parameters.